The Skyshield Landing Pad, normally used for Warhammer 40k, looked like a perfect Necromunda building to me. It's a really excellent kit, with only a few parts to put together. Here's the first of some pictures of it.

I modified the corners so that there are ladders to climb up on it. The four holes already have ladders, so that works for Necromunda.

The whole thing is drybrushed simple 'Russ Grey' and some of the surface is 'Leadbelcher' -- new GW paints. But the standout parts are the hazard-striped Imperial Aquilas. I used thin tape to mask them, and painted them in black and yellow stripes. Then I went in by hand and touched them up to get them very sharp. I continued the Russ Grey within the eagles, then used a micropen to outline them in black. I always wanted to try those techniques and I think they worked!

Note that painting the Imperial Aquila in hazard stripes is heresy. It implies the Emperor is dangerous.